Stars and constellations
'Stars and Constellation' What are constellations? (Sebastian Braddock) Constellations are patterns in the sky first identified by the ancient greeks which look vaguely like an abstract interpretation of either people or animals. These constellations are used both in astronomy, to help locate certain stars in the night sky via the use of star maps, and in astrology, to draw fictitious conclusions and extrapolations about the love life from the positions of the stars in relation to your star sign at any point of the year. There are 88 internationally approved constellations, with 48 of those having been named and described by Ptolemy in his 2nd century Almagest, and many more regionally approved ones, such as Aboriginal Australian constellations, Hindu constellations and Chinese ones. The more renowned constellations include Orion, Taurus, Ursa Major, and the big dipper. Identify North Star (Finn Lindemann) Characteristics: Polaris is the biggest star in the constellation of Ursa Minor (small bear). It marks, as the name already points out, the north. The distance from the earth to the star is roughly 343 light years away. So for all we know the star may already be dead. The polar star can be called a giant star due to its huge mass. The polar star has many names, such as: Cynosūra, from the Greek κυνόσουρα"the dog’s tail" (reflecting a time when the constellation of Ursa Minor "Little Bear" was taken to represent a dog). The famous name Polaris, Steadfast star, or the most known name, North Star. 1. Locate the Big Dipper in the northern sky. The big Dipper is easy to find, as it is firstly big and furthermore has a very distinctive shape. Depending upon the time of the year constellation of stars may be shifted in different directions as it rotates around the Lodester. 2. Locate the two stars that form the outer edge of the Big Dipper, as shown in the diagram. 3. Draw an imaginary line straight through the two stars of the dipper and towards the Ursa Minor. The line will point very close to the handle of the Little Dipper. 4. The brightest star in the Little Dipper is at the end of the tail. This is the North Star. How to find the Big Bear: Ursa Major is highest in the sky in the spring and lowest in the autumn. This constellation is a circumpolar constellation, which means it travels closely around the North Star; it is always above the horizon never rising or setting; it can be seen any time of the year, high or low in the sky. The big dipper is inside the big bear. So when you have found the bear, you can easily see the big dipper at the bottom. Orion The Hunter (Sebastian Braddock) Possibly the most famous and easy to find of all the constellations, Orion the hunter is most prominent in the northern hemisphere from November to February. Famous for his three starred belt, it has been depicted as a hunter ever since the time of Ptolemy, and possibly before that. The most visible star in the constellation is Rigel, a Blue Supergiant which depicts the left foot, but it is close to the supernova stage. The second brightest star is Beltegeuse, which is a massive red supergiant which is also close to explosion. It is often depicted as hunting the Taurus, as shown in the above picture. Taurus Taurus is one of the 12 zodiac constellations, and is one of the oldest constellations, having been used to mark the location of the sun during the spring equinox since the early bronze age, and has been identified as a bull in the cultures of ancient Babylon, Egypt and Greece. As with Orion, it is most prominent in the northern hemisphere during winter. Its most visible star is Alderbaran, which is arabic for the follower (of the pleiades). It is noted for its bright red hue. It is useful because it can be used to find the location of the pleiades, by drawing a line through Bellatrix in Orion through Aldebaran to the Pleiades. Pleiades The Pleiades, named after the 7 sisters of greek mythology which subsequently gave their name to the french renaissance era poetry club know as La Pleiade, are a group of 9 stars (the 2 extra stars been called after the two parents, Atlas and Pleione). Like Orion and Taurus, they are most visible in the northern hemisphere in winter, and are one of the most recognizable sights in the night sky. Astronomers estimate that the cluster will last for another 250 million years, after which they will disperse as a result of gravitational activity in the region. The majority of the stars are bright blue in colour. Cassiopeia (Louis Kos) The constellation, Cassiopeia, was found by Ptolemy in the 2nd Century, and is named after the Queen Cassiopeia in Greek Mythology. It is bordered by Andromeda (south), Perseus (southeast) and Cepheus (north). The constellation is opposite the big dipper, and it is the most visible in early November. It is made up of 5 stars, and it forms it ‘W’ shape. Gemini The constellation, Gemini, was also found by Plotemy in the 2nd Century. Gemini is Latin for ‘twins’, and the constellation is named so because it looks like two twins, who are named Castor and Pollux (Greek Mythology). The times where Gemini is most visible are in January and February. Star Maps Star maps are used to identify stars, galaxies and constellations more easily. The oldest star chart that we know of dates from 32,500 B.C and it was discovered in 1879. However, the Chinese were the first to make an official star manuscript in around 400 B.C. Around 300 years later, the Greeks categorised these constellations in grids, namely by the astronomer Hipparchus. Sailors in the middle Ages, used stars for direction (e.g. North Star), but they can also be used to determine which month it is, because some stars/constellations are only seen at some parts of the year, and some stars are much brighter during some parts of the year than other parts, such as Cassiopeia or Gemini. As shown to the right, the mapping of stars has been going on since far before modern times, with the greeks being the first to use known shapes in the stars to navigate around. This map from China also demonstrates that astronomy was far from constrained to only the western cultures. The following map is a good example of a modern star map, with several very familiar zodiac signs such as Virgo and Cancer being shown.